GreenHouse: Hawaiian Snow

I'm new to this thread and am researching strains. Can you confirm whether or not the H. Snow can yield pounds if grown outdoors? I am using 21 gallon pots with soil and perilite outdoors and I was wondering if I could get some poundage (more than one or two dried) from this plant? I ask that question because I saw some master grower with pics of H. Snow and it looked to be several feet above him in height and it yielded something like 5 pounds so they claimed. I am wondering if that's possible or not. Can you let me know please?

Also...question about coco coir. Does that stuff swell up and retain water or does it require you to go to your outdoor site every couple of days to rewater? I need to find out the answer to this question...